بررسی نقش نیکل در کاهش اثرات تنش خشکی گیاه Fortuynia garcinii

Serpentine soils are dry and contain rather high levels of nickel (Ni).To obtain a better understanding of drought tolerance by Ni in serpentine plants, a hydroponic trial was designed to compare the effects of Ni on growth factors, Ni uptake or translocation and some physiological parameters in the serpentine plant, Fortuynia garcinii (Burm.f.), under PEG simulated drought stress (3 levels). After 45 days, half number of vessels received 10 µM Ni for 8 days, and then plants ± Ni were exposed to drought stress for 8 days. The result indicating Ni treatment improved only slightly RWC, and Ni accumulation of root was consistently higher than shoot. The main reason for this action related to low translocation factors for this metal that showing this plant was more tolerant to plant-internal Ni. Photosynthetic pigments increased under drought stress treatments, but the treatments with Ni were consistently lower in compare same treatments without Ni in this serpentine plant. Phenolic compounds, water soluble carbohydrate, Glycine betaine and proline were also increased by Ni application under PEG simulated drought stress indicating that Ni improved the osmotic adjustment ability and enhance the antioxidant capacity. It is hypothesized that Ni could improve the drought tolerance of the serpentine plant by enhancing water utilization capability, osmotic adjustment and the abilities of antioxidative defense.